IR Training Flight Last Night

[Ghery]

3 nights in a row and I've been up with the CFII. Wednesday night in the 182, electrical problems caused us to cut it short. Plane is going in for annual, so they'll look at that as well. Thursday (OLM-FHR-OLM) and last night (OLM-PAE-OLM) in the Arrow. The question relates to last night.

The Arrow is /U. The only IFR bird in the club without DME. The initial plan for last night was to make the ILS approach to 16R at PAE. Take a look at the approach plate. ILS or LOC/DME to 16R. But the notes (both NACO and Jepp) say that simultanious reception of the localizer and DME are required. I understand that for the LOC/DME option, but the ILS? You can identify the IAF using a cross radial from CVV VOR. JUGBA would be identified by GS intercept or the OM (which is not monitored, so use it at your own risk). So, why is DME required for the ILS?

Plan B, which we executed was the VOR 16R approach (attached). All you need is a VOR receiver. Of course, the radar vectors made for a serious turn to the left to intercept the outbound radial to set up for the procedure turn. Intercepted the radial, dropped to 1100 MSL and drove along until lined up with the runway. T&G and back to OLM, shot the ILS 17 to minimums, ditched the foggles and landed. DME or Radar required for that one, we had radar vectors.

Oh, and until I burned a bunch of gas from the right tank it was seriously right wing heavy. No illumination on the AI (I'm going to call the maintenance officer and squawk that) and other than having a working DG it was like flying partial panel. CFII put his light on the AI and things smoothed out nicely. And, why did I file a route from OLM to PAE? SEA APP gave me radar vectors up and back. Oh well, that was good practice, too. And, it was clear and a million, or so say the weather types. I missed the view for some reason.

Happy New Year.

 

[HPNPilot1200]

So, why is DME required for the ILS?

I don't believe DME is required for the ILS 16R. The note just points out that fixes on the localizer reference PAE for DME. Usually, you receive DME off of the localizer frequency/channel but in this case if you were flying the LOC/DME approach, you have to use PAE for DME reference (to identify each fix) and therefore simultaneous reception of both the localizer (I-PAE) and VOR (PAE) for DME are required. The two antennas are not co-located.

See the attached image with red boxes (my emphasis).

 

[Ghery]

No question about why you would need both the LOC and VOR to get DME information while tracking the localizer. Makes perfect sense for the LOC/DME approach. But the note doesn't seem to limit itself to that option on the plate and I don't understand why DME would be required for the ILS option when the IAF can be identified with a cross bearing from CVV and the other fix coinsides with GS intercept. Oh well, one more argument for getting the club to put DME in the Arrow when they get around to removing the inop ADF receiver (original equipment that belongs in a museum) and either fixing or removing the inop autopilot.

 

[HPNPilot1200]

No question about why you would need both the LOC and VOR to get DME information while tracking the localizer. Makes perfect sense for the LOC/DME approach. But the note doesn't seem to limit itself to that option on the plate and I don't understand why DME would be required for the ILS option when the IAF can be identified with a cross bearing from CVV and the other fix coinsides with GS intercept. Oh well, one more argument for getting the club to put DME in the Arrow when they get around to removing the inop ADF receiver (original equipment that belongs in a museum) and either fixing or removing the inop autopilot.

According to the instrument procedures handbook, chapter 5, page 5-15 states:

In some cases, other types of navigation systems, including
radar, are required to execute other portions of the
approach or to navigate to the IAF (for example, an NDB
procedure turn to an ILS, or an NDB in the missed
approach, or radar required to join the procedure or identify
a fix). When ATC radar or other equipment is required
for procedure entry from the en route environment, a note
is charted in the planview of the approach procedure chart
(for example, RADAR REQUIRED or ADF
REQUIRED).

When radar or other equipment is required
on portions of the procedure outside the final approach
segment, including the missed approach, a note is charted
in the notes box of the pilot briefing portion of the
approach chart (for example, RADAR REQUIRED or
DME REQUIRED).

My emphasis in bold. The note on the PAE ILS or LOC/DME RWY 16R is in the "notes box" which would indicate that DME is required outside the final approach segment including the missed approach, but that doesn't exactly make sense (see below).

Since "DME" is included in procedure title under LOC/DME, it is required equipment along the final approach segment when executing the LOC/DME approach. WEBVE (IAF) can be identified by cross-radial and I cannot see any reason why DME would be required on the approach outside the final approach segment.

Given that information, my thought is that the note is there simply to clarify that simultaneous reception of I-PAE and PAE is required on the LOC/DME approach. Reviewing other ILS or LOC/DME approaches, it seems only those which use a different nav source for DME seem to have those notes (exact same phrasing) in the notes box.

 

[Ghery]

Jason,

That's my point. If flying the LOC/DME approach you clearly need DME and you need two separate receivers as the DME is off the VOR while the localizer is off a different source. When it comes to the ILS I can identify every fix needed without DME, so why would I need it? Neither my CFII or I can figure it out.

Oh well, I got good experience using the VOR 16R approach, instead. I can shoot ILS approaches without leaving home.

 

[azure]

Ghery, I think Jason is saying that not only do you not need it for the ILS, but the note isn't supposed to be taken to imply that you do. Stuff in the notes section doesn't necessarily apply to both the LOC/DME and ILS approaches, though I agree that it doesn't seem to make a distinction. But it COULD be read as only pointing out that the DME is from PAE and not I-PAE, and so you have to be able to receive both at the same time if you need DME (which you do for the LOC-only approach, but don't for the ILS).

I don't know if this helps or not... or if it even needs to be said.

 

[HPNPilot1200]

When it comes to the ILS I can identify every fix needed without DME, so why would I need it? Neither my CFII or I can figure it out.

I've done some digging and this is what I've found.

FAA 8260.19D (Flight Procedures and Airspace) Par 855 states:

DME frequencies are paired with the frequencies of the VOR, localizer, or MLS. When a non-paired DME is used in a VOR/DME, ILS/DME, etc., procedure, simultaneous reception of both facilities must be assured. This requires a note indicating the DME location and the identification of both facilities: “Chart note: DME from XYZ VORTAC. Simultaneous reception of I-ABC and XYZ DME required.”

FAA 8260.3B (Change 18 eff. 11/12/99) aka Terps Manual states:

Paragraph 161 changes the approach procedure naming convention. Instrument landing system (ILS) procedures utilizing distance measuring equipment (DME) will no longer have DME in the procedure name. If DME is required to support ILS localizer minimums, the chart will be noted to indicate DME is required for localizer (LOC) final.

....

Par 161.
ILS procedures do not require DME to fly the final approach, even if a DME fix has been substituted for one of the marker beacons, therefore, ILS procedures shall not be named ILS/DME.

From these documents, it appears the note "DME from PAE VOR/DME. Simultaneous reception of I-PAE and PAE DME required" only exists on the chart because a non-paired DME is used in the LOC/DME procedure, therefore DME is not required on the ILS RWY 16R approach.

 

[gismo]

From these documents, it appears the note "DME from PAE VOR/DME. Simultaneous reception of I-PAE and PAE DME required" only exists on the chart because a non-paired DME is used in the LOC/DME procedure, therefore DME is not required on the ILS RWY 16R approach.

Jason, I believe you are entirely correct. If DME were required for some portion of the ILS (e.g. the miss) the note would read "DME Required", not the text about simultaneous reception. And while DME should never be required to fly the final segment of an ILS, I'm pretty certain that there are a few where DME is needed, either for getting to the final, or for the miss but neither of those situations would require DME in the approach title.

Has anyone ever seen an approach titled "ILS/DME"?

 

[HPNPilot1200]

I'm pretty certain that there are a few where DME is needed, either for getting to the final, or for the miss but neither of those situations would require DME in the approach title.

Correct. Anytime DME is required for procedure entry from the enroute environment and/or outisde the final approach segment including the missed approach, a note is placed on the chart, but since DME is never required on the final segment of an ILS, it should never be in the procedure title (ie. "ILS/DME")

Has anyone ever seen an approach titled "ILS/DME"?

Yes, there are a few out there. Most of the ILS/DME charts I've seen are outside the United States, but there are still a few published in the US which haven't been updated since 1999 which is when TERPs removed "ILS/DME" from the title naming convention.

The ILS/DME RWY 11 at CEC is an example of an approach that still exists but hasn't been revised to conform with the new naming convention.

 

[Ghery]

Jason,

Thanks for that research. It makes perfect sense. The ILS would have been easier than the LOC approach we flew, but for training the LOC was a better choice anyway. We still need to get a DME put in that airplane (in place of the inop museum piece ADF and inop autopilot). An approach certified GPS would be nice, but I've already helped finance one for the 172. Oh well...

Thanks again.